A popular device for handling large amounts of information in a data processing system is the data storage library. These systems store and manage large numbers of cartridges containing magnetic tape on which data is recorded. Typically, a data storage library is comprised of arrays of uniquely identified storage cells, each cell being formed to contain a single tape cartridge. The cell arrays each hold a plurality of tape cartridges, and each tape cartridge has some kind of identifying information, such as a label or bar code. Typically, the arrays surround a robotic arm which has an optical system, for selecting cartridges, and is operable to locate a particular storage cell and retrieve and transport a tape cartridge therefrom.
Given the large capacity of data storage libraries, there is a continual need for an operator to load and unload cartridges from the library. One conventional technique is to implement a small access port which consists of a bank of storage cells mounted to a panel which rotates out from the storage area to present itself to an operator on the outside of the library enclosure. This technique is time consuming, since the access port must be opened many times to accomplish a full capacity load. In addition, the storage capacity of the library is reduced by the number of fixed storage cells replaced by the panel. Furthermore, such an access port often requires additional, costly motorized components.
For mass loading and unloading of large numbers of cartridges, more direct access to the cartridges contained within the library, such as through an access door, is preferable. However, each array is usually positioned so that the front of the array, the side from which the cartridges may be identified and accessed, faces the robotic arm. Since the arrays are typically mounted in close proximity to each other and surrounding the robotic arm, the arrays adjacent the access door have their backs facing the operator, denying the operator access to the cartridges or visibility of the cartridge identification labels.